The objective of the study was to characterize and interpret the shallow (to a depth of approximately 5,000 ft) three-dimensional geology and preliminary hydrogeology of the Questa area. The focus of this report is to compile existing geologic and geophysical data, integrate new geophysical data, and interpret these data to construct three, detailed geologic cross sections across the Questa area. These cross sections can be used by the Village of Questa to make decisions about municipal water-well development, and can be used in the future to help in the development of a conceptual model of groundwater flow for the Questa area. Attached to this report are a location map, a preliminary geologic map and unit descriptions, tables of water wells and springs used in the study, and three detailed hydrogeologic cross sections shown at two different vertical scales. The locations of the cross sections are shown on the index map of the cross section sheet.
The Capitan Reef is a fossil limestone reef of middle Permian age that is dramatically exposed along the southeast flank of the Guadalupe Mountains in Eddy County, New Mexico, reaching its maximum elevation in west Texas, in Guadalupe Mountains National Park. In New Mexico, the reef serves as the host rock for the Big Room in Carlsbad Cavern. A few miles northeast of Carlsbad Caverns National Park, the reef dips into the subsurface and passes beneath the city of Carlsbad, where it forms a karstic aquifer that is the principal source of fresh water for that community (Land and Burger, 2008). The Capitan Reef continues in the subsurface east and south into Lea County, then south for ~150 miles to its southeasternmost outcrop in the Glass Mountains of west Texas.
Two Bureau of Geology scientists, in collaboration with scientists at the United State Geological Survey, have discovered similarities between ground water systems that formed ore deposits 10 million years ago and modern ground water in the Rio Grande Rift. They reported their work in an invited presentation at the 2000 Annual Meeting of the Geological Society of America.
Dr. Virgil Lueth, mineralogist/ economic geologist, and Lisa Peters, senior lab associate at the New Mexico Geochronological Research Lab, have been studying the mineral jarosite in ore deposits from Chihuahua, Mexico, to Albuquerque.
In support of development of a 50-year water plan for New Mexico, the Interstate Stream Commission has tasked the New Mexico Bureau of Geology & Mineral Resources with convening a group of 8 water and climate research experts as an Advisory Panel. Their task is to prepare a consensus study report on the current state of knowledge of how climate conditions and water resources may vary across our state during the next 50 years.
The Roswell Artesian Basin occupies over 4,000 square miles in the lower Pecos Valley in Chaves and northern Eddy Counties, and is one of the most intensively farmed regions in the state outside the Rio Grande Valley (Welder, 1983; Land and Newton, 2008). The eastern margin of the basin occurs just east of the Pecos River; the northern boundary is approximately defined by Macho Draw north of Roswell; and the southern end of the basin is located at the Seven Rivers Hills north of Carlsbad. The western margin of the basin is not as well-defined, but is usually located west of Roswell on the Pecos Slope near the Chaves-Lincoln County Line. The basin derives virtually all of its irrigation and drinking water from groundwater stored in a karstic artesian limestone aquifer contained within the Permian San Andres and Grayburg Formations, and from a shallow unconfined aquifer composed of Tertiary-Quaternary alluvial material deposited by the ancestral Pecos River. The Roswell Basin has been described by many workers as a world-class example of a rechargeable artesian aquifer system (e.g., Fiedler and Nye, 1933; Havenor, 1968).
This study focused on the shallow aquifer that occurs in the dune field with depth-to-water ranging from 1 to 3 feet below interdunal surfaces. We used hydrologic and geochemical data to identify water sources that contribute to the shallow groundwater system in the dune field and to assess how this system responds to water level fluctuations in the adjacent regional basin-fill aquifer. Hydrologic modeling was used to assess the effects of projected additional groundwater pumping in Alamogordo on the shallow dune aquifer on the Monument.
The agricultural economy of Union County in northeastern New Mexico is highly dependent on groundwater. Ongoing drought, large new groundwater appropriations both within the county and in adjacent parts of Texas, and large water level declines in wells have led to concern amongst county residents over groundwater supplies. This report documents the finding of a hydrogeology study to better understand the aquifers utilized in east-central Union County. The study began in 2010 and covers 650 square miles, from north of Clayton to south of Sedan, and east to the state line. The study was jointly sponsored by Northeastern Soil and Water Conservation District (NESWCD), the Aquifer Mapping Program of the New Mexico Bureau of Geology and Mineral Resources, and Healy Foundation.
The Mesilla Basin is one of the southernmost basins of the Rio Grande Rift system, extending from south-central New Mexico across state and international boundaries into west Texas and northern Chihuahua, Mexico. The hydrology of the Mesilla Basin region has been subject to extensive investigations for over a century (e.g., Slichter, 1905; Theis, 1938; Sayre and Livingston, 1945; Conover, 1954; Leggat et al., 1962; Hawley et al., 1969; King et al., 1971; Wilson and White, 1984; Hawley and Lozinsky, 1992; Nickerson and Myers, 1993; Kennedy et al., 2000), as summarized by Hawley et al. (2001), who is paraphrased here. The eastern margin of the Mesilla Basin is defined by the Organ-Franklin-Juarez mountain chain, and the western margin by fault block and volcanic uplands of the East Potrillo Mountains and West Potrillo basalt field. The Robledo and Doña Ana Mountains define the northern end of the Mesilla Basin. The northeast end of the basin is transitional with the Jornada del Muerto Basin. The southern basin boundary with the Bolson de los Muertos in northern Chihuahua state is less well-defined. The entrenched Mesilla Valley of the Rio Grande crosses the eastern margin of the Mesilla Basin, where the cities of Las Cruces, NM, El Paso, Texas, and Juarez, Mexico exploit groundwater resources from the basin aquifers. Regional groundwater and surface water flow is to the southeast toward El Paso, through a gap separating the Franklin Mountains from Sierra Juarez to the south.
Several thousand water-level measurements spanning over 50 years, from over a thousand wells, were used to create aquifer lifetime projections for the High Plains aquifer in eastcentral New Mexico. Lifetime projections were made based on past water-level decline rates calculated over ten- and twenty-year intervals. Projected lifetimes were calculated for two scenarios. One scenario is the time until total dewatering of the full saturated thickness of the aquifer, and the other scenario is the time until a 30-ft saturated thickness threshold is reached, which is the minimum necessary to sustain high-capacity irrigation wells. Agricultural water use has largely determined water-level decline rates in the past. Assuming future decline rates match those of the past ten to twenty years, the two scenarios may be viewed as the usable aquifer lifetime for domestic and low-intensity municipal and industrial uses, and the usable lifetime for large-scale irrigated agriculture.
